The distribution of power among several loads presents certain challenges. This can be particularly true in environments where there is a limited amount of available power, but where hardware complexity and duplication are disadvantageous.
For instance, in commercial aircraft, power having certain characteristics should be supplied simultaneously to numerous loads, from consumer power outlets for use in powering personal electronic devices such as laptops or cellular telephones to reading lights and seatback electronic displays. Previous aircraft power distribution systems typically involve the distribution of raw aircraft power from a head-end device such as a power management system or circuit breaker, through a side wall disconnect panel to a first seat group. Power is then distributed from the first seat group to additional seat groups through seat-to-seat cabling that carries the power required by seat mounted power conversion units, which in turn provide power to a passenger interface at household voltage and frequency. Power carried through such seat-to-seat distribution networks is often 115 volt alternating current (VAC), three-phase power of either fixed (400 Hz) or variable (360-800 Hz) frequency. Seat power converters are necessary to convert this power to 110 VAC 60 Hz or other voltages to power passengers' electronic devices.
Systems of this type require seat power converters that are suitable for use with an aircraft platform, and thus they preferably have certain capabilities and characteristics, such as power factor correction, a low electromagnetic interference (EMI) signature, low current harmonics and a low load demand variation. Thus, the seat power converters often contain complex circuitry, such as energy storage and filtering devices, to adequately meet these requirements. In addition to the disadvantages inherent in complex circuitry, undesirable heat is generated at the point of conversion by processing power locally at the passengers' seats.
Often, various power management functions are accomplished alongside power distribution. Certain load distribution and management systems (LDMSs) have been previously disclosed. U.S. Pat. No. 5,754,445, titled “Load Distribution and Management System,” by Jouper et al. relates to such systems. U.S. Pat. No. 6,046,513, titled “Load Distribution and Management System,” by Jouper et al., U.S. Pat. No. 8,295,065, titled “System control by use of phase rotation signaling” by Jouper, and U.S. Pat. App. No. 2012/0,139,341, titled “System control by use of phase rotation signaling,” by Jouper, each relate to LDMSs. The disclosures of U.S. Pat. Nos. 5,754,445, 6,046,513, 8,295,065 and U.S. Pat. App. No. 2012/0,139,341 are hereby incorporated by reference herein in their entirety.
The subject matter of the present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.